Re: [Mesa3d-dev] OSMesaCreateContext missing in XFree86 4.0

[Howard <ho...@me...>]

Harry Overs wrote:
> 
> My guess is that because you are using geforce mesa is replaced by the UTAH
> GLX which is based on SGI's OpenGL ???
> 
This seems to be the case. It looks like X 4.0 uses the SGI based glX,
which therefore excludes the OSMesa functions. We will need a hack in
this glX.

Brian Paul wrote:
> 
> OS/Mesa is not in XFree86 4.0 in any form.  However, this is something
> I was thinking about yesterday and I think it would be possible to add
> this feature to XFree86's libGL.  Basically, I'd provide a new library,
> libOSMesa.so which you'd have to link with.  It would patch into the
> libGL.so dispatcher and work like stand-alone Mesa.
> 
This would be ideal! Otherwise we would need a wrapper around the glX
dispatcher that would not be nearly as efficient.

> > Also, is there any known reason why glXChooseVisual in XFree86 4.0 Mesa
> > would not find an XPixmap with RGB, depth and stencil?
>                     ^^^^^^^
> You mean a GLXVisual, I think.
> 
Yes, right. It turns out that the request is sensitive to the single or
double buffer parameter, and it's only available in a double buffer for
some reason.

> Use glxinfo to list your GLX visuals.  You might not have a stencil
> buffer, I'd guess.
> 
It seems odd, but apparently our board only has stencils in double
buffer mode, according to glxinfo, or the current GeForce drivers only
support double buffered stencils.

> > We are on a Linux x86 libc6 based system, using a GForce 256 AGP card.
> 
> Using NVIDIA or the UtathGLX drivers?
> 
We are the drivers that are packaged with the current (March)
distribution of XFree86 4.0. So I think that means the UtahGLX.

-- 
Howard Luby     ho...@me...,  Ph:(248)540-2251, Fax:(248)540-3138
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